Tuesday, February 07, 2006



A doomed garden

Scientists in New Guinea have discovered hundreds of new species in a remote part of the New Guinea rainforest they described as "as close to the Garden of Eden as you're going to find on Earth". Unfortunately, it's a discovery tinged with tragedy, because many of these species are in all likelihood doomed to extinction in the near future. And the reason is global warming. This doomed garden is on the upper slopes of the Foja mountains, which rise to up to 2200m above sea level. But as global temperatures rise, their habitat will be forced up the mountain, shrinking all the way. If we are lucky, some of it will survive as a tiny island in the clouds. If we are unlucky, they'll run out of mountain.

This problem isn't limited only to New Guinea. It affects every alpine and subalpine environment in the world. And it has been going on for some time. In The Weather Makers, Tim Flannery recounts how, as a young scientist in 1981, he climbed Mt Albert Edward, one of New Guinea's highest peaks. At the boundary between jungle and subalpine tussock, he noticed that the jungle was advancing:

In the leaf litter on the forest floor, I was surprised to find the trunks of dead tree-ferns. Tree-ferns grew only in the grassland, so here was clear evidence that the forest was colonising the slope from below. Judging from the distribution of the tree-fern trunks, it had swallowed at least thirty metres of grassland in less time than it takes for a tree-fern to rot on the damp forest floor - a decade or two at most.

The reason, he recounts later, is to do with climate change. The temperature drops slightly over half a degree for every hundred meters you go up a mountain. This means that an increase in air temperature of a single degree will allow the treeline to climb up to 200 metres. We're already physically committed to at least one degree of global warming, and if we do nothing and continue "business as usual", then that becomes at least three degrees (I say "at least" because these are lower bounds, not upper ones). That's 200 - 600m less mountain for alpine species to inhabit. And when the mountain you live on is only 2200m high, and you're already more than halfway up, it doesn't leave much room to maneuvre.

7 comments:

Bring on the rampant genetic engineering... if you want a strange animal - make it.

Posted by Genius : 2/07/2006 07:43:00 PM

I'm not an environmentalist because nobody's made a case for it being in my interest so far. These are two honest questions for which I'm seeking non-emotional answers. Perhaps someone here can answer them and help change my mind.

My first question is: Why is it important to have every last species survive? Some species aren't useful to man. By what right should anybody be forced to change their behaviors to protect useless animals?

The second question is: Why isn't global warming our goal, not our fear? If we could push global temperatures even just 3-4 degrees upward then crops would do better, people would be more comfortable through most of the world, and there would be more usable or forestable land.

Posted by Anonymous : 2/08/2006 06:28:00 AM

Anon:

1) Every last species won't survive, and no-one who knows even a modicum of biology has every claimed that they should. A continual turnover of species is a natural part of the evolutionary process. The point is that in the modern (human) era, species are going extinct at a rate that is basically unprecedented except during mass extinction events, a la major asteroid strikes. If the sheer moral repugnance of that being our fault fails to move you, consider that most of the world's food comes from a handful of genetically impoverished species, while the major pool of variation in the wild steadily disappears. Consider also the potential for new drugs (anti-cancer, or antibiotics that actually work against drug-resistant diseases) that lie in all those soon-to-be-gone ecosystems. As a final point to make you care, be aware that we really have no idea about what consequences removing all these species has on ecosystem function. And we are not at all removed from the functioning of ecosystems. The collapse of many inshore fisheries highlights this.

2) Which crops? Where? The ones currently growing close to sea-level? Or in regions that are not currently hurricane-prone but could be if the sea where warmer? Or in countries affected by El Nino... Climate change is about more than temperature, and we know too little about the consequences to be saying "she'll be right". Get out a topographic map and figure out what a 2 metre sea level rise would do to your favourite city.

I don't call myself an environmentalist either, but these issues you raise have moved beyond being only of concern to fringe loonies. Some of them will have an impact during our lifetimes.

BTW, I/S, are you aware that climate change is not actually Flannery's speciality, and he was commissioned to write that book? He put a few noses out of joint by not even bothering to talk to Australian members of the IPCC during his research... when he says "I've read the research", he's being a tad economical with the truth ;)

Posted by Chris : 2/08/2006 11:02:00 AM

Anon: To back up Chris's point (2), a rise in average global temperature doesn't mean that it gets warmer everywhere at once. The effects will be distributed unevenly throughout the global climate; some areas (e.g. Europe) may in fact get cooler while others heat up. Some will get wetter, some drier. In the long view, we'll move our intensive agriculture to the areas it is best; in the short-term, that process will be characterised by drought, famine, and death, and possibly even a long-term decrease in the carrying capacity of the planet.

Look at Australia: their best farmland (such as it is) has been suffering a near-permanant drought for the last decade because of shifts in the El Nino Southern Oscillation. Meanwhile, other parts of Australia are getting wetter. Their cities are on the verge of drying up and blowing away. That's climate change right there.

Chris: Of course, putting noses out of joint doesn't necessarily equate to being wrong. The problem so far seems to be that the topic is too big even for him...

Posted by Idiot/Savant : 2/08/2006 11:51:00 AM

I haven't yet tackled that climate book myself (The Future Easters was good), but I hear that it's not really well organised, and a bit lacking in the indexing and reference fields. You can't please everyone, of course.

I think the out-of-joint noses were more a result of "I've talked to the experts"... except for the world authorities who were right in front of him!

Posted by Chris : 2/08/2006 12:51:00 PM

Flannery's book was probably designed to make information about climate change accesible to the non specialist and it succeeded in that I think. He didn;t have a lot that was good to say about the IPCC though.

"as dull as dishwater and confines itself to the lowerst common denominator"...thats what he had to say about the IPCC's 2001 report.

He went on to say that their pronouncements "don't represent mainstream science or even good science, but lowest common denominator science - and of course even that is delivered at glacial speed."

That all suggests that they are irrelevent or almost an impediment to the world acting on climate change.

According to Flannery their findings are delivered by consensus...a consensus that requires the agreement of the major oil producing and polluting nations who have a vested interest in watering down the IPCC's findings.

His advice was that "if the IPCC says something you'd better believe it...and allow for the liklihood that things are far worse than it says they are."

its no wonder their noses are out of joint.

Mike

Posted by Anonymous : 2/08/2006 08:49:00 PM

Hmmm, bit of a broad brush he's applied there.

As I understand it, the individual chapters of the IPCC report are written by different groups. While there has to be consensus within that group, the different chapters don't have to all say the same thing (obiviously, with each chapter having a different focus).

Flannery isn't the first person to call the IPCC too conservative (Bjorn Lomborg said something similar, if you wish to poke that anthill). The point is that they have to be credible, and their "upper bounds" scenarios are actually pretty frightening -- something like 6 degrees rise over the next century.

Posted by Chris : 2/09/2006 10:57:00 AM